Revolving-hook construction for sewing-machines.



R. s. KELSO,

REVOLVING HOOK CONSTRUCTION FOR SEWING MACHINES, APPLICATION man FEE-21,1910. RENEWED JAN. 31-. 1911.

"1 235 323 I I PatntedJulySl, 1917.

2 SHEETSSHEET 1- Zak/l If/32h Arm/mm R. S. KELSO. REVOLVING HOOK CONSTRUCTION FOR SEWING MACHINES. APPLICATION FILED FE'B. 21,1910- RENEWED JAN. 31. I917. 1,235,323,, I Patented July 31,1917.

2 SHEETSSHEET 2- ATTORNEYS RALPH SIMPSON KELSO, 0F CLEVELAND, GHIO.

REVOLVING-HUGE GQNSTRUCTION FOR SEVJING-MAGHINES.

Specification of Letters Patent.

Patented July 31, 12 917.

Application filed February :21, 1910, Serial No. 545,051. Renewed January 81, 1917. Serial No. 145,814.

To all whom it may concern:

Be it known that l, RALPH S. KnLso, a citizen of the United States, and a resident of Cleveland, in "the county of Cuyahoga and State of Ohio, have invented a new and Improved Revolving-Hook Construction for Sewing-Machines, of which the following is a full, clear, and exact description.

T he invention relates to sewing machines of the high-speed lock-stitch type, wherein the needle thread is carried around the bobbin case by a revoluble loop-carrier in which the bobbin case is stationarily contained.

The object of the invention is to provide an improved thread loop carrier and bobbin case, the parts being so constructed that the bobbin case can be easily and quickly removed from and replaced in the thread loop-carrier, and in which little, if any, lateral thrust or rolling of the thread is caused by the passage of the needle thread loop thereabout.

lhe invention consists in the construction and combination of parts as hereinafter fully described and pointed out in the claims.

Reference is to be had to the accompanying drawings forming a part of time specification in which similar characters of reference indicate corresponding parts in all the views.

Figure l is a front end elevation of a sewingimachine having the improvement applied thereto;

Fig. 2 is a front face view of the bobbin case and loop carrier partly in section;

Fig. 3. is a longitudinal vertical section of the same on the line 3-3 of Fig. 2;

Fig. d is an inner face view of the bobbin case;

Fig. 5 is a side view of the same;

Fig. 6 is an outer face view of the bobbln case;

Fig. 7 is. a face view of the bobbin case holder or base;

Fig. 8 is a side view of the bobbin case holder or base;

Fig. 9 is an outer face view of the bobbin case holder retaining ring;

Fig. 10 is an inner face view of the same;

Fig. 11 is an outer face view of the loop carrier; and

Fig. 12 is a side view of the same.

Referring to the drawings, 20 is the base of the machine frame from which rises the housing 21 which carries the head 23, all of which may beof any well known construction. The improvement which consists of the thread loop carrier and the bobbin case are mounted below the base 20 in the usual and well known way.

The threaddoop-carrier, shown in detail in Figs. 11 and 12, is constructed with a stem or socket 7 7 for receiving and securing it to a revolving shaft of the machine and is provided with a dished head 78 having an outwardly-extending flange 9, the flange being concentrically slotted for a short distance, as indicated at 80, with the forward end of the slot terminating at the outer end of a slot 81 formed in the periphery of the head and inclining rearwardly with respect to the direction of rotation,

the slots 80 and 81 producing a threadloop-tongue 82, the point of the tongue 82 projecting slightly beyond the face of the flange. A bobbin case holder 83, shown in detail in Figs. 7 and 8, of dished construction to approximately conform to the shape of the thread-loop-carrier, has an external flange 84 approximately centrally arranged and revolubly received in a groove 85 formed in the face of the loop carrier at the inside of the flange 79, the outer side of this flange being closed when the bobbin case holder is assembled with the thread loopcarrier, by a segmental retaining ring 86, as shown in detail in Figs. 9 and 10, this ring being secured to the flange 79 of the threadloop-carrier by screws, and having recesses 87 on its inner face adjacent to the inner edge, where the flange 84 bears, somewhat deeper recesses 88 being formed in the thread-loop-carrier in the opposite wall of the groove, these recesses being designed to catch the lint of the fabric sewed and provide an absorbent for the oil, whereby the flange 8% is lubricated to a nicety. The retaining ring 86 terminates a substantial distance at the front and back of the hook 82, part of the front wall of the groove in the thread-loop-carrier being formed at the inneredge of the flange 79, adjacent to the hook 82, as shown in dotted outline in Fig. 2. At the top of the bobbin case holder adjacent to its outer edge is a vertically-extending tongue 89 having a recess 90 in its outer face, the tongue being spaced slightly from the outer face of the thread-loop-carrier and retaining-ring 86 to permit of the passage of the hook 82, a needle opening 91 being provided in the top of the bobbin case holder directly back of the tongue, to provide for the passage of the thread 100 in the path of the hook. The tongue 89 0 the bobbin case holder is of a considerable width and of, a length to extend above the thread hook so that it serves as aguard to prevent the loop of the thread from being caught by the hook while passing the said tongue upon its idle revolution. lhe bottom or head of the bobbin case holder forms the inner head of the bobbin case 92 when the latter is assembled, as shown in Fig. 3, and is slightly spaced from the inner wall of the head of the loop carrier to pro vide a thread passage, 93. From the center of the bobbin case carrier extends an outwardly projecting stem 94 having a depressible spring catch 95 at its outer end, the stem 94 receiving a tubular stem or bearing 96 projecting inwardly from the outer head of the case, the outer rounded end of the tubular stem being engaged by the projecting end of the spring catch 95, the inner end of the'tubular bearing being also flared or rounded so that the bobbin case may beassembled with the bobbin case holder or removed therefrom, without depressing the catch with the finger, for this purpose. The front head of the bobbin case has an upwardly-extending retaining tongue 97 received in and fitting the recess 90 in the retaining tongue of the bobbin case holder, the tongue 97 having a threadopening 98, through which the thread passes from the bobbin 99 after first lead ing through a thread-opening 100 formed in the cylindrical surface of the bobbin case directly at'the rear of the tongue. An outwardly and rearwardly-inclined thread slit 101 leads to the opening 100 to facilitate the insertion of the thread, and a similar slit 102 extends through the base of the tongue to the thread-opening 98, for a like purpose. To the front of the bobbin case is secured by a screw 103, a tension spring 104, the spring overlapping the threadopening 98 and binding the thread to the retaining tongue 97 of the case, the thread passing from under the tongue in an upward direction. By adjusting the screw 103, the tension on the thread may be varied as desired. When the bobbin case is in operative position, relative revolution between it and the bobbin case holder is prevented by the tongue 97 and the bobbin case holder is stationarily held by a split-ring 105, which, as best shown in Fig. 1, has its opposed ends or jaws connected together by an ofiset bridge piece 105 and engaging and receiving the opposite edges of the retaining tongue 89, the ring being suitably and removably secured at the bottom by a screw 106..

When the needle descends with the thread and-begins to retract, casting out the loop, the latter is picked up by the book 82 and carried about the case, the loo spreading equally at each side of the obbin case holder, whereby there is substantially no lateral thrust on the flange 84. When the hook has revolved slightly more than half a revolution and reaches the bottom of the case, the loop slipsofi and passes around the holder, the inner portion of the loop passing through the thread pasage 93, looking about the thread from the bobbin and drawing the latter tight to the material sewed as the needle thread is drawn upwardly by the thread take-up lever.

Having thus described my invention, I claim as new and desire to secure by Letters Patent:

1. in a sewing machine,-a dished thread loop carrier, a dished bobbin case holder in the carrier and having a tongue spaced from said carrier, a bobbin case in the holder and having a tongue extending in front of the tongue of the said holder and having a thread opening therein, and a tension spring secured to the said case and arranged to bear on the thread passing through said opening.

2. In a sewing machine, a rotary thread loop carrier, a bobbin case holder in the loop carrier, and having a recessed tongue, a bobbin case within the holder and having a thread opening passing through the top thereof, and a retainingtongue extended upwardly from the outer portion of the case and fitting in the recess of the tongue of the bobbin case holder, said tongue having a thread opening arranged toreceive the thread from the bobbin after it has passed through the'opening in the top of the case.

3. In .a sewing machine, a rotary thread loop carrier, a bobbin case holder in the.

loop carrier, and having a recessed tongue spaced from the loop carrier, a bobbin case removably held in the holder and having a thread opening passing through the side thereof, with a thread slit extending from the inner edge of the case to the opening, a tongue extended from the case adjacent to its front edge and fitting in the recess of the tongue of the bobbin case holder, said tongue'being provided with a thread opening, with a slit extended through the side of the tongue to the last-named opening, and a tension spring arranged to engage the thread adjacent to one of said openings.

4. In a sewing machine, a bobbin case holder having a tongue extended therefrom, provided with a recess in its front face, and a bobbin case removably fitting within the holder, having a retaining tongue arranged to be received in said recess and provided with a' thread opening.

5. in a sewing machine, a thread-loopcarrier, a bobbin case holder arranged within the carrier, having a tongue extended therefrom, provided with a recess, a bobbin case fitting within the holder and having a tongue arranged to be received in the recess of the tongue of the holder, and a stationary ring having jaws extending on opposite sides of the tongue of the holder and adapted to be engaged by said tongue.

6. In a sewing machine, a thread-loopcarrier having a dished slotted head provided with an external slotted flange, the slots of the head and flange forming a thread-loop-hook, the head of the carrier having a groove arranged internally adjacent to its outer face, a bobbin case holderarranged within the dished head of the carrier and having an external flange received in said groove, and a retaining ring removably secured to the outer face of the flange of the carrier and forming a portion of the outer wall of the said groove, with another a bobbin ease holder in the carrier and having a tongue, and a bobbin case in the holder and having a tongue extending in front of the tongue of the holder, the tongue of the holder being of considerable width and of a length to extend above the thread hook, whereby it serves as a guard to prevent the loop of the needle thread from being caught by the hook while passing the said tongue upon its idle revolution.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

RALPH SIMPSON KELSO.

Witnesses:

G. B. DAVIS, OBED C. BILLMAN. 

